Reaction Motors XLR99-RM-1 rocket engine
Reaction Motors Division of Thiokol's XLR99-RM-1 was the throttleable, single-chamber rocket engine developed specifically for the piloted X-15. NASA records anhydrous ammonia and liquid oxygen propellants, 19,200–57,200 lbf at 40,000 feet, 256–276 s specific impulse, and first XLR99-powered flight in November 1960; the engine is recorded as a retired historical model with no additional installation inferred.
Identity
- Aliases
- XLR99-RM-1XLR-99XLR99
- Domains
- aviationspaceflight
- Identity Level
- variant
- Kind
- liquid-rocket-engine
- Name
- Reaction Motors XLR99-RM-1 rocket engine
- Status
- retired
Details
- Description
- Reaction Motors Division of Thiokol's XLR99-RM-1 was the throttleable, single-chamber rocket engine developed specifically for the piloted X-15. NASA records anhydrous ammonia and liquid oxygen propellants, 19,200–57,200 lbf at 40,000 feet, 256–276 s specific impulse, and first XLR99-powered flight in November 1960; the engine is recorded as a retired historical model with no additional installation inferred.
- Propellants
- anhydrous ammonialiquid oxygen
- Rocket Specs
- Chamber Count
- 1
Links
Assets & Meta
- Creation Time
- August 15, 2026 at 03:27:55 UTC
- Updated Time
- August 15, 2026 at 03:27:55 UTC
Other
- Sources
- Accessed Date
- 2026-08-14
- Note
- NASA's X-15 monograph identifies the exact XLR99-RM-1 designation, its development for the piloted X-15, ammonia/LOX propellants, 19,200–57,200 lbf thrust at 40,000 feet, 256–276 s specific impulse, and single-thrust-chamber architecture.
- Publisher
- NASA
- Title
- Hypersonics Before the Shuttle
- Accessed Date
- 2026-08-14
- Note
- NASA's X-15 reference confirms the later XLR-99 installation, throttleable rocket operation, and up-to-57,000-pound thrust on the research aircraft.
- Publisher
- NASA
- Title
- X-15 Hypersonic Research Program
- Accessed Date
- 2026-08-14
- Note
- NASA's flight-research history records XLR99-RM-1 operating experience in the X-15 program and its first flight in November 1960.
- Publisher
- NASA Technical Reports Server
- Title
- Fifty Years of Flight Research